Crystal devices are used in various fields and in various devices such as computers, communications devices, artificial satellites, and measuring instruments. In particular, crystal devices are essential components for the generation of vibrations having a frequency for controlling signal transmission and reception in a mobile communications terminal.
A crystal device uses a crystal blank as a vibration medium. A vibration frequency of the crystal blank may be changed according to an ambient temperature, and thus, the crystal device requires a function of compensating for frequency variations according to changes in temperature.
Accordingly, a temperature compensated crystal oscillator (TCXO) has been proposed, but in this regard, a structure of the TCXO may be relatively complicated and there may be limitations on miniaturizing the TCXO.